Alert archive / Louisiana / Mesoscale Discussions in 2015

Mesoscale Discussion 2028

December 23, 201544 parishes in Louisiana; 26 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at Dec 23, 2015, 2:34 AM CST for 44 parishes in Louisiana; 26 counties in Mississippi. It was in force for 86 min.

The area

The outline as issued.

The facts

Issued: Dec 23, 2015, 2:34 AM CST (08:34 UTC)
Expired: Dec 23, 2015, 4:00 AM CST
In force: 86 min
Issued by: the Storm Prediction Center
Chance of a watch: 20%

All 70 counties

Acadia Parish, LA, Allen Parish, LA, Ascension Parish, LA, Assumption Parish, LA, Avoyelles Parish, LA, Caldwell Parish, LA, Cameron Parish, LA, Catahoula Parish, LA, Concordia Parish, LA, East Baton Rouge Parish, LA, East Carroll Parish, LA, East Feliciana Parish, LA, Evangeline Parish, LA, Franklin Parish, LA, Grant Parish, LA, Iberia Parish, LA, Iberville Parish, LA, Jefferson Davis Parish, LA, Lafayette Parish, LA, Lafourche Parish, LA, LaSalle Parish, LA, Livingston Parish, LA, Madison Parish, LA, Orleans Parish, LA, Ouachita Parish, LA, Pointe Coupee Parish, LA, Rapides Parish, LA, Richland Parish, LA, Saint Charles Parish, LA, Saint Helena Parish, LA, Saint James Parish, LA, Saint John the Baptist Parish, LA, Saint Landry Parish, LA, Saint Martin Parish, LA, Saint Tammany Parish, LA, St. Mary Parish, LA, Tangipahoa Parish, LA, Tensas Parish, LA, Terrebonne Parish, LA, Vermilion Parish, LA, Washington Parish, LA, West Baton Rouge Parish, LA, West Carroll Parish, LA, West Feliciana Parish, LA, Adams County, MS, Amite County, MS, Claiborne County, MS, Copiah County, MS, Covington County, MS, Franklin County, MS, Hinds County, MS, Humphreys County, MS, Issaquena County, MS, Jefferson County, MS, Jefferson Davis County, MS, Lawrence County, MS, Lincoln County, MS, Madison County, MS, Marion County, MS, Pike County, MS, Rankin County, MS, Scott County, MS, Sharkey County, MS, Simpson County, MS, Smith County, MS, Walthall County, MS, Warren County, MS, Washington County, MS, Wilkinson County, MS, Yazoo County, MS

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 00:00Z, 8.6 hours before the alert went out and 180 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 84 J/kg
Mixed-layer CIN: -116 J/kg
Mixed-layer LCL: 765 m above ground
0-6 km bulk shear: 45 kt
0-1 km storm-relative helicity: 211 m²/s²
0-3 km storm-relative helicity: 193 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Dec 22, 10:17 PM CST	Mesoscale Discussion	SPC	Bienville, Bossier, Caddo, Claiborne, De Soto, Natchitoches and 4 more	2 hr
Dec 22, 11:20 PM CST	Mesoscale Discussion	SPC	Jefferson, Lafourche, Plaquemines, St. Mary, Terrebonne	115 min
Dec 23, 12:06 AM CST	Tornado Watch	SPC	Bienville, Bossier, Caddo, Claiborne, De Soto, Grant and 9 more	7 hr
Dec 23, 4:39 AM CST	Mesoscale Discussion	SPC	Bienville, Bossier, Caddo, Claiborne, De Soto, Grant and 10 more	2 hr
Dec 23, 6:20 AM CST	Tornado Watch	SPC	Bienville, Bossier, Caddo, Claiborne, De Soto, Lincoln and 3 more	7 hr
Dec 23, 10:12 AM CST	Mesoscale Discussion	SPC	Bienville, Bossier, Caddo, Claiborne, De Soto, Lincoln and 3 more	93 min
Dec 23, 10:58 AM CST	Mesoscale Discussion	SPC	Morehouse, West Carroll	2 hr
Dec 23, 11:57 AM CST	Tornado Watch PDS	SPC	East Carroll, Franklin, Madison, Morehouse, Richland, West Carroll	9 hr
Dec 23, 12:48 PM CST	Mesoscale Discussion	SPC	East Carroll, Morehouse, West Carroll	57 min
Dec 23, 1:33 PM CST	Mesoscale Discussion	SPC	East Baton Rouge, East Feliciana, Saint Helena, Washington	57 min
Dec 23, 2:17 PM CST	Tornado Watch	SPC	Attala, Choctaw, Clarke, Clay, Copiah, Covington and 29 more	6 hr
Dec 23, 2:49 PM CST	Mesoscale Discussion	SPC	Alcorn, Benton, Bolivar, Calhoun, Coahoma, DeSoto and 19 more	86 min
Dec 23, 5:12 PM CST	Mesoscale Discussion	SPC	Clarke, Covington, Forrest, George, Greene, Jasper and 19 more	63 min

Nearby

Mesoscale Discussions in Louisiana, 2015 Mesoscale Discussions in Mississippi, 2015 Every mesoscale discussion in 2015

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive.